Since 1982, there has been a move to Thermal Sprayed Aluminum (TSA) coating in the “splash zone” of offshore structures. Our experience indicates that an experience applicator, good surface preparation and quality of wire combined to achieve required thickness and apply the sealer to seal the entire surface.
04022 2004 CP
Desmond K.K. Tiong, Shell International; Halimah Pit, Sarawak Shell Berhad
Historically the coatings used in the splash zone have been coal tar epoxy or glassflake polyester/epoxy. Since 1982, oil and gas industry has moved towards Thermal Sprayed Aluminum (TSA) coating for protection of steel structures in the splashzone. In 1995, SM-EP investigated the potential of TSA coatings on offshore structures in the South China Sea. Experience from other operators indicated that TSA coatings, when properly applied and with the use of specific sealer systems, will provide a service life in excess of 30 years with zero maintenance required. It also posses good mechanical properties and is ideal for use anywhere within the offshore environment where, with conventional coatings, it is difficult to carry out repair. In 1997 SIEP engaged a consultant firm in UK, to carry out literature review on the use, performance and life cycle costs of TSA coatings for offshore structures. The findings based on 'in-service' experience with TSA coatings indicated long-term corrosion protection together with the cost savings based on Life Cycle Cost calculations, and appeared to demonstrate the advantage of the TSA system over traditional coating systems. TSA coatings pilot project was applied in F23K-A in 1999. To date, SM-EP has used TSA coatings on three offshore structures. Our experiences showed that the most important factors were to engage experience applicator, ensure good surface preparation, quality of wire used, strict adherence to the environmental conditions, achieve the required minimum thickness and apply the sealer to seal the entire surface.
Keywords: Splash Zone, Thermal Sprayed Aluminum,offshore structures, coatings, surface preparation